Weft tensioning and cutting means

ABSTRACT

A weaving machine comprising a weft-inserting device on one side and means carried by the reed on the opposite side adapted to catch, grasp and tension the weft yarn inserted through the weaving shed, wherein the means for catching, grasping and tensioning the wefts comprises an air injector, the suction opening of which is located at the end of the weft inserting passage way and the outlet of which is bent towards the beating up line in the cloth, a slit in the side wall of said air injector extending from the suction opening along a portion of the length of the injector into the beating up direction of the reed, a thread clamp being located in a fixed position between the lateral edge of the cloth and the air injector, such that with the reed in the beating up position the thread clamp is positioned in the path of the end portion of the inserted weft extending from the lateral edge of the cloth towards the air injector.

United States Patent 1191 Vermeulen et al.

[ Aug. 26, 1975 l l WEFI' TENSIONING AND CUTTING MEANS [75] Inventors:Geert Jan Vermeulen; Hubertus Henricus Aarts, both of Deurne,Netherlands [73] Assignec: Ruti-Te Strake B.V., Deurnc,

Netherlands l Filed: Aug. 20, 1973 1 1 Appl. No.: 390,144

Mullekom 1 139/194 Yano et al. 139/194 Primary E.\'uminerHenry S. JaudonAtmrney, Agenl, or Firm-Marshall & Yeasting l ABSTRACT A weaving machinecomprising a weft-inserting device on one side and means carried by thereed on the 0pposite side adapted to catch, grasp and tension the weftyarn inserted through the weaving shed, wherein the means for catching,grasping and tensioning the wefts comprises an air injector, the suctionopening of which is located at the end of the weft inserting passage wayand the outlet of which is bent towards the beating up line in thecloth, a slit in the side wall of said air injector extending from thesuction opening along a portion of the length of the injector into thebeating up direction of the reed, a thread clamp being located in afixed position between the lateral edge of the cloth and the airinjector, such that with the reed in the beating up position the threadclamp is positioned in the path of the end portion of the inserted weftextending from the lateral edge of the cloth towards the air injector.

3 Claims, 3 Drawing Figures PATENTEU AUEZSIHYS SI'EU 1 OF BACKGROUND OFTHE INVENTION This invention relates to a weaving machine comprising aweft-inserting device on one side and means car ried by the reed on theopposite side adapted to catch, grasp and tension the weft yarn insertedthrough the weaving shed.

A weaving machine of this type has been proposed, in which the means forcatching, grasping and tensioning the weft yarn comprises a catchingelement carried by the reed and cooperating with a stationary clampingmember. During the beating movement of the reed the weft which has beeninserted into the weaving shed is tensioned due to the cooperationbetween the catching and clamping members. It is a drawback of thisdevice that the weft, after it has been beaten up into the cloth andafter the reed has started to move to its retracted position may becomeuntensioned, so that the ultimate interlacing may be insufficientlytight.

SUMMARY OF THE INVENTION It is a main object of the invention toovercome this drawback. For this purpose in accordance with the presentinvention the means for catching, grasping and tensioning the weftscomprises an air injector, the suction opening of which is located atthe end of the weft inserting passage way and the outlet of which isbent towards the beating up line in the cloth, a slit in the side wallof said air injector extending from the suction opening along a portionof the length of the injector into the beating up direction of the reed,a thread clamp being located in a fixed position between the lateraledge of the cloth and the air injector such, that with the reed in thebeating up position the thread clamp is positioned in the path of theend portion of the inserted weft extending from the lateral edge of thecloth towards the air injector.

With this device the air injector effects a uniform tensioning of thesuccessively inserted weft threads. Due to the injector being bent inthe beating up direction, the said end portion of the inserted weftextends obliquely from the lateral edge of the cloth. As a result ofthis the tensioning injector will keep the inserted weft, after it hasbeen beaten up into the cloth and upon initiating of the retractingmovement of the reed, in a tensioned state. Thus there is ample time forthe thread clamp to engage the portion of the inserted weft extendingbeyond the lateral edge of the cloth, thereby maintaining the tensionedstate and the position of the weft beaten up into the cloth, e.g. untilthis weft has been ultimately interlaced into the cloth as a result ofthe changing of the weaving shed.

In a preferred embodiment of the invention a guide piece is carried bythe reed and mounted so as to be slidably adjustable in the weftinserting direction, said guide piece having a catching channel inalignment ous weaving widths by simply slidingly adjusting the guidepiece.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a perspective view of apart of a weaving machine according to the inention;

FIG. 2 shows a plan view of a part of the cloth, as well as a partlysectional plan view of the tensioning injector and the thread clamp andthe cutting device cooperating therewith, with the reed in the beatingup position and FIG. 3 represents a vertical cross-sectional view alongthe line III-III of FIG. 2.

With reference to FIG. 1, 1 and 2 each designate a side portion of theframe of the weaving machine. 3 designates the reed, which may bereciprocated according to the arrow I about an axis not shown, between abeating up position and a retracted position, the latter being shown inthe drawing.

The reed is formed, in a manner known per se, by a plurality of reedblades 4, disposed side by side, with their lower ends inserted in thereed beam 5 and with their upper ends held together by a mounting rail6.

7 indicates the weaving shed which is confined by the upper warps 8, thelower warps 9 and the reed blades 4. The cloth is indicated at 10 andpasses through the temple 12 mounted on a stationary part 11 of themachine. 13 indicates the beating up line, i.e. the line along which aweft thread inserted through the weaving shed is beaten up by the reedwhen the latter is moved to its beating up position.

The weft insertion is effected eg by means of a flowing fluid, such aspressurized air. For this purpose in the embodiment shown in thedrawings a nozzle 14 is applied on one side of the weaving machine.

The transportation of a weft thread by means of the nozzle 14 in facttakes place through a tunnel 15, which is confined by the U-shapedbeating up edges of the reed blades 4, said tunnel being longitudinallyopen towards said beating up line 13. If desired a number of auxiliarynozzles may be applied across the weaving width and mounted onto thereed so as to assist in transporting the weft thread through the weavingshed. Such auxiliary nozzles, however, have not been shown in thedrawing.

At the end of the reed remote from the nozzle 14 a guide piece 16 isslidably mounted on the rail 6 by means of a bracket 16a. This guidepiece 16 has a projecting rib 17, fitting in the reed tunnel 15 andprovided with a catching passage way 18, the end of which facing thenozzle 14 merges into the reed tunnel 15, while its opposite end is bentin the beating up direction and merges into an opening 18a. The catchingpassage way 18 communicates along its entire length with a lateral slit18b facing towards the beating up line 13.

Depending on the desired weaving width the guide piece may be fixed at alarger or smaller distance from the nozzle 14 onto the reed.

With reference to FIG. 2 and 3, the device for tensioning a weft thathas been inserted through the weaving shed 7, comprises an air injector19, which may be of a well-known construction. This air injector ismounted onto the guide piece 16 in such a way that the suction opening19a of said injector coincides with the opening 18a of the guide piece,while the suction passage confined by the outer tube 19b of the injectorconstitutes an extension of the catching passage way 18 of the guidepiece. The injector 19 is positioned with its axis parallel to thelateral edge 20 of the cloth. The injector 19 may be connected as at 190to a compressed air hose on the side facing away from lateral edge 20 ofthe cloth in order to force an annular jet of air through the annularnozzle 19f. The injector 19 has a slit 19d forming an extension of theslit 18b of the guide piece 16.

Beside the edge 20 of the cloth there is a support 21 which may be fixedto the breast beam, not shown in the drawing. On this support thebearing block 22 for the shaft 23 of the rotary cutting member,indicated at 24, is mounted. The cutting member 24 cooperates in ascissors-like manner with the stationary cutting member 25, carried by afixed frame portion 26. The rotary cutting member 24 is driven by theshaft 23 which in turn is driven, through transmission means not shown,by an intermediary shaft coupled with the main shaft of the weavingmachine.

The support 21 also carries a solenoid-controlled thread clamp 28. Thisthread clamp comprises a clamping lever 30 which is rotatably mountedabout a shaft 29 and is provided with a clamping pad 30a cooperatingwith a clamping surface on the lower side of the fixed frame portion 26.A spring 32 extending between a fixed screw 31 on one hand and a shortvertical extension of the clamping lever 30 on the other hand tends tokeep the clamping lever in its opened position. An actuating arm 33 isconnected with the clamping lever 30. Upon energization of the solenoidindicated at 34 the actuating arm 33 is pulled against the action of thespring 32 and urges the clamping lever 30 into its clamping position inwhich it is shown in FIG. 3.

In FIGS. 2 and 3 the reed is in its beating up position. As shown moreparticularly in FIG. 2 the end portion of the inserted weft thread wprojecting beyond the lateral edge 20 of the cloth extends obliquelytowards the injector 19 which keeps the weft thread w under tension. Theprojecting weft thread portion abuts the end 19e of the slit 19d, sothat the position of the projecting weft thread portion is exactlydefined. As is also shown in FIG. 2 the operative parts of the threadclamp and of the cutting device are positioned in the path of theprojecting weft thread portion. The suction opening of the conduit 35for sucking off the cut weft thread end portions is also positioned inthis path. 37 designates the mouth of said conduit, in which an injector36 provides for the desired suction power.

A weft thread inserted through the weaving shed 7 by means of the nozzle14 while the reed is taking its retracted position (FIG. 1) will, at thecompletion of the inserting phase, at its leading end be deviated by theguide piece 16 in the beating up direction (warp direction) andintroduced into the air injector 19, the latter exerting the desiredtension on the so caught weft thread. The inserted weft w is then beatenup in this tensioned state into the cloth by the reed. As mentionedbefore the portion of the weft thread w projecting laterally beyond theedge of the cloth extends obliquely in the cloth rolling up direction atthe time the beating up operation takes place. Instantly after thebeating up operation the solenoid 34 is energized, due to which thethread clamp 30, 30a which at that time is in the path of the projectingweft thread portion, is closed and clamps the said thread portion in itsstill tensioned state. The energization of the solenoid 34 is con tinueduntil the changing of the shed has taken place and as a consequence theweft thread beaten up into the cloth has been also interlaced. In themeantime the reed and the air injector 19 have returned to the retractedposition, whereby the laterally extending weft thread portion which isclamped in the stationary clamp 30a, has been prevented from followingthe re tracting movement of the reed and the air injector 19 andtherefore has been withdrawn from said injector through the slit 19d.Before the deenergizing of the solenoid 34 and thus before thediscontinuing of the clamping action of the thread clamp, the movablecutting member 24 is rotated upward from the inclined position shown inFIGS. 2 and 3, so that the cutting member 24 swings against the lowerside of the weft thread w, whereby the projecting weft thread endportion is cut between the movable cutting member 24 and the overlyingstationary cutting member 25 at a short distance from the edge 20 of thecloth. The timing of the actuation of the movable cutting member 24 iscorrespondingly chosen. In the meantime the injector 36 is energized andthe weft thread portion to be cut off is in the sphere of influence ofthe suction opening 37 of the conduit 35 and will be sucked into thelatter as soon as the cutting off has taken place and the thread clamphas become inoperative.

It is finally remarked that in the catching passage way 18 an opticalweft thread detection device may be installed, such as diagrammaticallyshown at 38 in FIG. 2. A correctly inserted weft thread will, when it isdeviated at its leading end in the catching passage way 18 and pulled bythe tensioning injector 19, pass such detection device and then producethe required signal for initiating the following weft insertion.

We claim:

1. A weaving machine comprising a reciprocable reed, two sheets of warpthreads which are momentarily held in diverging planes to form with thereed a weaving shed, a weft-inserting device on one side of the machineand means carried by the reed on the opposite side of the machineadapted to catch, grasp and tension a weft yarn inserted through theweaving shed, characterized in that the means for catching, grasping andtensioning the weft comprises an air injector, the suction opening ofwhich is located at the end of the weft inserting passage way and theoutlet of which is bent toward the beating up line in the cloth, a slitin the side wall of said air injector extending from the suction openingalong a portion of the length of the injector in the beating updirection of the reed, a thread clamp mounted on the machine in a fixedposition, between the lateral edge of the cloth and the path ofreciprocation of the air injector, such that with the reed in thebeating up position the thread clamp is positioned in the path of theend portion of the inserted weft extending from the lateral edge of thecloth toward the air injector.

2. A weaving machine according to claim 1, characterized in that a guidepiece mounted on the reed is slidably adjustable in the weft insertingdirection and has a catching channel in alignment with the weftinserting path, said catching channel at the end remote from the weftinserting device being bent in the beating up direction, and beinglaterally open along its entire length in the beating up direction, theair injector being transversely connected to the catching channel of theguide piece, and the slit of said injector forming an extension of theopen side of the catching channel.

3. A weaving machine according to claim 1 in which a cutting device, athread clamp and a device for sucking off the cut thread ends aremounted on the side of the machine remote from the weft insertingdevice,

positioned between the lateral edge of the cloth and the path ofreciprocation of the tensioning injector, in the path of the weft threadportion extending from the edge characterized in that the operativeparts of the cutting 5 of the Cloth toward the tensioninginjectordevice, the thread clamp and the sucking off device are

1. A weaving machine comprising a reciprocable reed, two sheets of warpthreads which are momentarily held in diverging planes to form with thereed a weaving shed, a weft-inserting device on one side of the machineand means carried by the reed on the opposite side of the machineadapted to catch, grasp and tension a weft yarn inserted through theweaving shed, characterized in that the means for catching, grasping andtensioning the weft comprises an air injector, the suction opening ofwhich is located at the end of the weft inserting passage way and theoutlet of which is bent toward the beating up line in the cloth, a slitin the side wall of said air injector extending from the suction openingalong a portion of the length of the injector in the beating updirection of the reed, a thread clamp mounted on the machine in a fixedposition, between the lateral edge of the cloth and the path ofreciprocation of the air injector, such that with the reed in thebeating up position the thread clamp is positioned in the path of theend portion of the inserted weft extending from the lateral edge of thecloth toward the air injector.
 2. A weaving machine according to claim1, characterized in that a guide piece mounted on the reed is slidablyadjustable in the weft inserting direction and has a catching channel inalignment with the weft inserting path, said catching channel at the endremote from the weft inserting device being bent in the beating updirection, and being laterally open along its entire length in thebeating up direction, the air injector being transversely connected tothe catching channel of the guide piece, and the slit of said injectorforming an extension of the open side of the catching channel.
 3. Aweaving machine according to claim 1 in which a cutting device, a threadclamp and a device for sucking off the cut thread ends are mounted onthe side of the machine remote from the weft inserting device,characterized in that the operative parts of the cutting device, thethread clamp and the sucking off device are positioned between thelateral edge of the cloth and the path of reciprocation of thetensioning injector, in the path of the weft thread portion extendingfrom the edge of the cloth toward the tensioning injector.